Class MaybeQueryInterceptor

Namespace

Trellis.EntityFrameworkCore

Assembly

Trellis.EntityFrameworkCore.dll

An EF Core query expression interceptor that automatically rewrites Maybe<T> property accesses in LINQ expression trees to their underlying storage member equivalents.

public sealed class MaybeQueryInterceptor : IQueryExpressionInterceptor, ISingletonInterceptor, IInterceptor

Inheritance

object

MaybeQueryInterceptor

Implements

IQueryExpressionInterceptor

ISingletonInterceptor

IInterceptor

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.ReferenceEquals(object, object)

object.ToString()

Extension Methods

MaybeExtensions.AsMaybe<T>(T)

MaybeExtensions.ToResult<TValue>(TValue)

NullableExtensions.ToResult<T>(T?, Func<Error>)

NullableExtensions.ToResult<T>(T?, Error)

AggregateTestMutator.ClearMaybeField<TEntity, TValue>(TEntity, Expression<Func<TEntity, Maybe<TValue>>>)

AggregateTestMutator.SetMaybeField<TEntity, TValue>(TEntity, Expression<Func<TEntity, Maybe<TValue>>>, TValue?)

Examples

With this interceptor registered, these LINQ expressions work directly:

// Natural LINQ — no explicit extension methods needed
context.Customers.Where(c => c.Phone.HasValue)
context.Orders.Where(o => o.SubmittedAt.GetValueOrDefault(DateTime.MaxValue) < cutoff)

// Specifications with Maybe<T> properties
public override Expression<Func<Order, bool>> ToExpression() =>
    order => order.Status == OrderStatus.Submitted
          && order.SubmittedAt.GetValueOrDefault(DateTime.MaxValue) < _cutoff;

Remarks

When registered, this interceptor allows natural LINQ syntax with Maybe<T> properties in queries and specifications, without requiring explicit extension methods like WhereHasValue or WhereLessThan.

Register by calling optionsBuilder.AddInterceptors(new MaybeQueryInterceptor()).

Methods

QueryCompilationStarting(Expression, QueryExpressionEventData)

Rewrites the query expression tree before compilation, replacing Maybe<T> property accesses with EF Core-translatable storage member references.

public Expression QueryCompilationStarting(Expression queryExpression, QueryExpressionEventData eventData)

Parameters

queryExpression Expression

eventData QueryExpressionEventData

Returns

Expression